Ultrasonic irradiation apparatus

ABSTRACT

An ultrasonic irradiation apparatus irradiates ultrasonic waves onto a wide area having three-dimensionally curved surfaces. An ultrasonic irradiator having a plurality of ultrasonic transducer is arranged in a plane. The position of at least a portion of the ultrasonic transducers is mutually and flexibly changeable in three dimensions. Ultrasonic transducers are installed on a surface of a flexible and/or elastic sheet member or net member. The ultrasonic irradiator may include a plurality of ultrasonic transducers formed on a flexible piezoelectric sheet member, including driving electrodes arranged on one surface and opposed electrodes arranged on another surface. The ultrasonic irradiator may be installed on or inside of a flexible planar bag containing a fluidic ultrasonic conductive medium. A mechanism is provided for moving or tilting the ultrasonic irradiator with respect to the object, or a band-holding member may be provided for fitting the irradiator to the object.

CROSS-REFERENCE TO RELATED APPLICATION

This application is the U.S. national phase of PCT application numberPCT/US01/16929, filed May 24, 2001, which further claims priority toU.S. patent application Ser. No. 09/578,024, filed May 24, 2000.

TECHNOLOGICAL FIELD

The present invention relates to an ultrasonic irradiation apparatus forirradiating, with ultrasonic waves, a wide area of an object to beirradiated such as a living body.

BACKGROUND ART

The inventor of the present invention conducted research and discoveredthat fats within a living body were decomposed (lipolysis) byirradiating the living body with ultrasonic waves having a specificfrequency. A patent application regarding an ultrasonic wave irradiationapparatus was filed and published as PCT Publication Number WO 99/39677on Aug. 12, 1999.

In the practice of the previous invention, it was required to irradiatethe living body with ultrasonic waves. The living body has widethree-dimensionally curved surfaces composed of complicated unevensurfaces such as, e.g., the abdominal region, the thighs, the buttocksor the chin. Therefore, it is difficult to evenly irradiate the surfaceof a living body with ultrasonic waves.

To solve such a problem, in the published international patentapplication, there was disclosed:

(1) an apparatus, having an ultrasonic transducer arranged on a sidewall of a bath tub, for irradiating a living body via hot water in thebath tub with ultrasonic waves generated by the ultrasonic transducer;

(2) an apparatus, having an ultrasonic transducer arranged on the bottomof a water chamber having an upper side thereof left open, forirradiating, with ultrasonic waves, a living body contacting the wateron the upper opening area via the water in the water chamber; and

(3) an apparatus, having an ultrasonic transducer arranged within ashower head, for irradiating, with ultrasonic waves, a living body viawater or hot water flowing out from the shower head.

It has been known to irradiate with ultrasonic waves for, e.g.,enhancing beauty, acceleration of blood circulation and for curingstiffness in the shoulder or lumbago, and some conventional ultrasonicirradiation apparatuses have been known for these purposes. Theconventional ultrasonic irradiation apparatus has a single ultrasonictransducer having a diameter of about 20 to 50 mm, and irradiation, withultrasonic waves, over a desired wide area of a living body is performedby scanning the living body surface with an acoustic output part of theapparatus.

In the conventional ultrasonic irradiation apparatus, ultrasonicallyirradiating the living body having three-dimensionally curved surfacesis easily conducted without large size equipment such as a bath tub, awater chamber or a shower system, because scanning can cover the livingbody surface to some extent. But, when the scanning area becomes wider,in the conventional system it requires a long time to scan wider areasbecause of the time required to manually scan the single ultrasonictransducer to accumulate the necessary irradiation dose (intensity ofirradiation×the accumulated time of irradiation) per unit surface area.Hence, the work load for an operator, such as a doctor, becomes heavier.

In the published international patent application, an apparatus has beendisclosed, having a single ultrasonic transducer and an acoustic lensarranged in front of the ultrasonic transducer, for irradiating a livingbody with ultrasonic waves through a bag containing an ultrasonicconducting medium such as, e.g., water or jelly. In the system of thepublished patent application, it is possible not only to make closecontact with a living body via the water bag, but also to expand thearea of irradiation greater than using a sole ultrasonic transducer, dueto a function of the acoustic lens, and thereby one is able toeffectively scan the living body.

However, in the case where the area to be scanned is wider, the systemdisclosed in the published international patent application has the sameproblems as the conventional ultrasonic irradiation apparatus. In otherwords, it takes a long time to scan wider areas and the load imposed onthe operator becomes heavier.

Further, in the apparatus for irradiating ultrasonic waves via a bagcontaining an ultrasonic conducting medium, the distance between theacoustic lens and a window portion of the bag, which outputs ultrasonicwaves and which is in contact with the living body, must become longerto make the irradiation area wider, and thus the amount of water isincreased. As the result, the pressure of the water weight istransferred to the living body, and it is difficult to make adjustmentsso as to partially support and lessen the pressure due to such weight.Further, in the apparatus for irradiating with ultrasonic waves via thebag containing the ultrasonic conducting medium, the position of theliving body to be irradiated with ultrasonic waves is limited because,if the irradiation direction to the living body is not vertical, theoutput window of the bag is greatly deformed by gravity and thereby itis difficult to scan smoothly.

DISCLOSURE OF THE INVENTION

An object of the present invention is to provide an apparatus capable ofeasily irradiating, with ultrasonic waves, a wide area of an objecthaving three-dimensional surfaces.

To accomplish the above object, an ultrasonic irradiation apparatusaccording to the present invention comprises an ultrasonic irradiatorincluding a plurality of ultrasonic transducers arranged in a planarpattern wherein at least a portion of the ultrasonic transducers aremutually and flexibly deformable in three dimensions. In the presentpatent application, the term of “flexibly deformable in threedimensions” also includes the meaning of “flexibly deformable in twodimensions.”

In the ultrasonic irradiation apparatus according to the presentinvention, an area within the object, where ultrasonic waves can beirradiated at one time, becomes considerably wider than in theconventional apparatus having a single ultrasonic transducer, becausethe plurality of ultrasonic transducers are arranged in a planarpattern. Thus, the load imposed on the operator can be reduced whenirradiating a wide area of the object with ultrasonic waves.

Further, in the ultrasonic irradiation apparatus according to thepresent invention, at least a portion of the plurality of ultrasonictransducers arranged in the planar configuration are mutually deformablein three dimensions. As a result, the ultrasonic transducers can befitted along the surface of the object having three-dimensionally curvedsurfaces, such as a living body, and the object can be evenly irradiatedwith ultrasonic waves.

The ultrasonic irradiation apparatus according to the present inventionis characterized in that the plurality of ultrasonic transducers arearranged on a flexible and/or elastic sheet member, so as to be mutuallydeformable in three dimensions. As examples of the flexible and/orelastic sheet member, several types of rubber sheet members, foamedrubber sheet members, such as expanded butylene or expanded silicon,fabrics or unwoven textiles may be applicable.

A sheet member having elasticity is preferable, although one having onlyflexibility may be used. In the case where the sheet member has onlyflexibility, the sheet member should have good flexibility in onedirection, but the sheet member should be difficult to be deformed in adirection transverse to the direction which is deformed first.

Therefore, it is preferable that the sheet member has a plurality oflinear recesses (this word is used interchangeable with the term “slot”hereafter) so that the sheet member is flexibly deformed based on bothedges of the linear recesses becoming apart from each other. Thereby,when the sheet member is deformed in a direction along the linearrecesses, the sheet can be also deformed in a direction transverse tothe linear recesses, and the position of the ultrasonic transducers canbe mutually deformed in three dimensions. The shape and width of thelinear recesses may be freely determined.

The linear recesses should be formed from one surface toward the othersurface in the sheet member, and may or may not penetrate though to theother surface.

Further, the ultrasonic irradiation apparatus according to the presentinvention is characterized in that the plurality of ultrasonictransducers are arranged on a net member having flexibility and/orstrechability, so that the position of the plurality of ultrasonictransducers is mutually deformable in three dimensions. As the flexiblenet member, a material is used that is composed of at least one type ofmaterial selected from a string, a band, a spring, a chain, and rodsthat are linked so as to be mutually rotatable.

Further, the ultrasonic irradiation apparatus according to the presentinvention is characterized in that the plurality of ultrasonictransducers making up the ultrasonic irradiator are composed of drivingelectrodes arranged on one surface of a flexible piezoelectric sheetmember and opposed electrodes arranged on the other surface of theflexible piezoelectric sheet member, facing each other. Hence, theposition in the plurality of ultrasonic transducers is mutuallydeformable in three dimensions. As the flexible piezoelectric sheetmember, a sheet member composed of an organic piezoelectric materialsuch as polyvinylidene fluoride (PVDF), or a sheet member composed of aplastic material kneaded with piezoelectric particulates, comprisingceramics such as Pb(Zr*Ti₃)O₃ (PZT), can be used.

The flexible piezoelectric material has a characteristic of goodflexibility in one direction, but when the flexible piezoelectricmaterial is deformed in the one direction, the flexible piezoelectricmaterial is difficult to be deformed in a direction transverse to thedeformed direction. Therefore, it is preferable that the flexibleorganic piezoelectric material has a plurality of linear recesses and isflexibly deformable based on the edges of the linear recesses movingapart from each other. Thereby, when the flexible organic piezoelectricmaterial is deformed in a direction along the linear recesses, thematerial can also be deformed in a direction crossing the linearrecesses, and the position of the ultrasonic transducers can be mutuallydeformed in three dimensions. The shape and width of the linear recessesmay be freely determined.

The linear recesses should be formed from one surface toward the othersurface in the piezoelectric material, and may or may not penetrate thepiezoelectric material through to the other surface.

In any one of the ultrasonic irradiators described above, it ispreferable that a soft material layer or a fluidic material layer, whichis composed of an ultrasonic conducting medium for transferringultrasonic waves to an object to be irradiated, be arranged between theultrasonic irradiator and the object. Thereby, an additional function,such as optional setting of temperature, can be achieved with the softmaterial layer or the fluidic material layer.

It is preferable, in the ultrasonic irradiator in which a plurality ofultrasonic transducers are arranged in a plane, or in any of theultrasonic irradiators described above, that said transducers bearranged on the surface of a planar bag which has a fluidic materialserving as an ultrasonic conducting medium and which has flexibility.Thereby, the ultrasonic irradiator and the planar bag can be integrated,and handling becomes easier.

Such a bag is deformable because the bag itself is flexible and containsthe fluidic material therein. However, it is applicable further toarrange a tube, channeling the outside of the bag and the inside of thebag, and a pump for changing a volume of the fluidic material in the bagover time, by adding/reducing the fluidic material through the tube.Thereby, the shape of the bag can be intentionally deformed.

In the case where an output plane (window) of ultrasonic waves of thebag is applied vertically to a living body, an offset of the outputplane due to blisters or inferior contact between the bag and the livingbody may be caused, because the fluidic material is pulled down toward abottom portion of the bag due to gravity and the like. Therefore, it ispreferable that the bag has a connection member for connecting aninternal upper plane and an internal bottom plane in the bag, and formaintaining a maximum distance between the internal upper plane and theinternal bottom plane at least within a predetermined range.

In the ultrasonic irradiation apparatus according to the presentinvention, a plurality of ultrasonic transducers being arranged inplane, or any one of the ultrasonic irradiators described above may bearranged on the inside of a flexible planar bag having at least oneflexible surface (window), and containing a fluidic material as theultrasonic conducting medium, for averaging a local intensity variationcaused by interference between the ultrasonic waves mainly of theadjacent transducers overlapping within the object, while irradiatingthe object having three-dimensionally curved surfaces, and alsoaveraging an uneven spatial distribution of the sonic field caused bythe arrangement of the ultrasonic transducers. The flexible planar bagmay also have elasticity. Then, in the ultrasonic irradiation apparatusaccording to the present invention, it is preferable that at least onesurface of the ultrasonic irradiator be arranged so as to be easilymoved along the plane portion of the flexible planar bag and/or so as tobe easily tilted to the plane portion of the flexible planar bag.Because the ultrasonic irradiator is arranged so as to be easily movedand/or tilted as described above, the position of the ultrasonictransducers in the ultrasonic irradiator with respect to an object canbe relatively changed. Thereby, it is possible to spatially average anyunevenness of the sonic field caused by overlap, as described above, aswell as any unevenness caused by the arrangement of the ultrasonictransducers.

The planar bag having at least one flexible plane is easily handled whena back plane opposed to the window plane for outputting ultrasonic wavesis made rigid. Also the rigid back can be a base member for moving ortilting the ultrasonic transducers. The planar bag having at least oneflexible plane comprises a plurality of straight recesses arrangedmutually in parallel on the back plane so as to be flexibly deformablein a direction transverse to the straight linear recesses. Thereby, theplanar bag can be deformed in the direction transverse the straightrecesses, and with respect to a curved surface along the straightrecesses, the flexibility of an output window can adaptively accommodatethe curvature. Then, the planar bag having at least one flexible planecan be fitted three-dimensionally with the object. In this case, theweight of the flexible planar bag becomes light because the deformationof the flexible plane, serving as the output window, becomes slight andthe thickness of the fluidic material can be kept thin.

In the ultrasonic irradiation apparatus according to the presentinvention, the soft material or the fluidic material serving as anultrasonic conducting medium is preferably a hot pack (i.e., a heatablehigh specific heat material) or a cold pack (i.e., a refrigeratable highspecific heat material). The effectiveness of irradiation by ultrasonicwaves with respect to the object can be improved by controlling thetemperature of the contacting surface of the soft material or thefluidic material, which has been heated or cooled previously. In thecase where the object is a human body, the tactile feeling of the objectcan be improved by previously heating or cooling the soft material orthe fluidic material.

The ultrasonic irradiation apparatus according to the present inventionis characterized in that the ultrasonic irradiation apparatus has aband-like holding member for fitting the ultrasonic irradiator to theobject. Because the ultrasonic irradiation apparatus has such a bandholding member, the ultrasonic irradiator can be held and fitted to theobject, and the load on the operator can be greatly reduced.

Then, the ultrasonic transducers are preferably arranged so as to beeasily moved, reciprocating along a length and/or width direction in theband-like holding member, to average a local variation of the sonicfield caused by interference of adjacent ultrasonic transducers, or toaverage an uneven spatial distribution of the sonic field caused by thearrangement of the ultrasonic transducers at the inside of the object.

The ultrasonic irradiation apparatus according to the present inventionis characterized in that the ultrasonic irradiator comprises means forbeing driven electrically by at least two or more drive systems, each ofwhich drives the plurality of ultrasonic transducers in mutuallydifferent electrical conditions. Thus, a spatial distribution ofintensity caused by interference at overlapping portions of each sonicfield of the ultrasonic transducers is averaged, without being fixedonly by a single drive system, while each ultrasonic transducer positionis mutually deformed in three dimensions.

In the ultrasonic irradiation apparatus according to the presentinvention, the ultrasonic irradiator comprises the aforementioneddriving means, so that each of the plurality of ultrasonic transducersare driven in mutually different conditions. Hence, the position onwhich ultrasonic waves from each ultrasonic transducer overlap withinthe object is constantly changed. Thereby, in the ultrasonic irradiationapparatus according to the present invention, the irradiation dose ofultrasonic waves inside the object is spatially averaged, and anexcessive or insufficient dose of irradiation at some specific portionwithin the object can be avoided.

In the ultrasonic irradiation apparatus according to the presentinvention, it is preferable that the ultrasonic irradiator comprises animpedance adjusting means for adjusting an output allocation to theplurality of ultrasonic transducers, so that each sonic field oftransducers forms a predetermined intensity ratio when each transducerposition is mutually deformed three-dimensionally, and wherein theimpedance adjusting means is arranged in parallel to each transducer orto a predetermined set of transducers. In the ultrasonic irradiationapparatus according to the present invention, the ultrasonic irradiationapparatus comprises the aforementioned impedance adjusting means, andthus it is possible to adjust the output allocation of each transducerso that the irradiation distribution of the ultrasonic waves within theobject becomes a specified or even distribution.

In the ultrasonic irradiation apparatus according to the presentinvention, the ultrasonic irradiator may have an approximately resonantinductance to each ultrasonic transducer, which is adjustable, so that asonic field from each ultrasonic transducer acquires a predeterminedintensity ratio, and the inductance may be arranged in series to eachultrasonic transducer, or to a set composed of a predetermined number ofultrasonic transducers. In the ultrasonic irradiation apparatusaccording to the present invention, the ultrasonic irradiation apparatuscomprises the adjustable inductance. Hence, it is possible to adjust theoutput allocation to each transducer so that the intensity distributionof the ultrasonic waves within the object becomes a specified or evendistribution.

The ultrasonic irradiation apparatus according to the present inventionis characterized in that the ultrasonic irradiator, having a pluralityof ultrasonic transducers arranged in plane on a surface of a rigidsheet member, is arranged inside of a planar bag which contains afluidic material as an ultrasonic conducting medium, and which has atleast one flexible plane surface. Thus, the ultrasonic irradiationapparatus is capable of contacting an object having three-dimensionallycurved surfaces, such as a living body, with the flexible plane surfaceof the planar bag. Therefore, even though a plurality of ultrasonictransducers are installed on the surface of the rigid sheet member inthe ultrasonic irradiator arranged inside the planar bag, it is possibleto easily irradiate with ultrasonic waves a wide area of an objecthaving three-dimensionally curved surfaces.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan figure showing an example of an ultrasonic irradiationapparatus according to a first embodiment of the present invention.

FIG. 2 is a cross sectional figure showing an example of usage, at thecorresponding cross section II-II depicted in FIG. 1, of the ultrasonicirradiation apparatus according to the first embodiment.

FIG. 3 is a cross sectional figure showing another example of usage, atthe corresponding cross section II-II depicted in FIG. 1, of theultrasonic irradiation apparatus according to the first embodiment.

FIG. 4 is a plan figure showing a first example of an ultrasonicirradiation apparatus according to a second embodiment of the presentinvention.

FIG. 5 is a plan figure showing a second example of the ultrasonicirradiation apparatus according to the second embodiment of the presentinvention.

FIG. 6 is a plan figure showing a third example of the ultrasonicirradiation apparatus according to the second embodiment of the presentinvention.

FIG. 7 is a plan figure showing a fourth example of the ultrasonicirradiation apparatus according to the second embodiment of the presentinvention.

FIG. 8 is a plan figure showing an example of an ultrasonic irradiationapparatus according to a third embodiment of the present invention.

FIG. 9 is a cross sectional figure showing the usage at the crosssection IX-IX depicted in FIG. 8, of the ultrasonic irradiationapparatus according to the third embodiment.

FIG. 10 is a cross sectional figure showing the usage at the crosssection X-X depicted in FIG. 8, of the ultrasonic irradiation apparatusaccording to the third embodiment.

FIG. 11 is a cross sectional figure showing an example of an ultrasonicirradiation apparatus according to a fourth embodiment of the presentinvention.

FIG. 12 is a cross sectional figure showing an enlarged primary portionof FIG. 11.

FIG. 13 is a cross sectional figure showing one example of an ultrasonicirradiation apparatus according to a fifth embodiment of the presentinvention.

FIG. 14 is a cross sectional figure showing an example of a structurefor movement of an ultrasonic irradiator, in the ultrasonic irradiationapparatus depicted in FIG. 13.

FIG. 15 is a cross sectional figure showing another example of astructure for movement of an ultrasonic irradiator, in the ultrasonicirradiation apparatus depicted in FIG. 13.

FIG. 16 is a cross sectional figure showing an example of a structurefor tilting an ultrasonic irradiator, in the ultrasonic irradiationapparatus depicted in FIG. 13.

FIG. 17 is a cross sectional figure showing another example of anultrasonic irradiation apparatus, according to the fifth embodiment ofthe present invention.

FIG. 18 is a cross sectional figure showing an example of a structurefor tilting an ultrasonic irradiator, in the ultrasonic irradiationapparatus depicted in FIG. 17.

FIG. 19 is a cross sectional figure showing still another example of anultrasonic irradiation apparatus, according to the fifth embodiment ofthe present invention.

FIG. 20 is a cross sectional figure showing an example of an ultrasonicirradiation apparatus, according to a sixth embodiment of the presentinvention.

FIG. 21 is a cross sectional figure showing another example of anultrasonic irradiation apparatus, according to the sixth embodiment ofthe present invention.

PREFERRED EMBODIMENTS OF THE PRESENT INVENTION

Embodiments of the present invention are described in detail byreferring to the attached figures as follows.

First, with reference to FIG. 1 through FIG. 3, an ultrasonicirradiation apparatus according to the first embodiment of the presentinvention shall be described.

The ultrasonic irradiation apparatus, according to this embodiment is anapparatus for irradiating a living body with ultrasonic waves, mainlyfor lipolysis, but it can be also used for other purposes such asacceleration of the bloodstream, infiltration of an endermic medicine,and so on. In the first embodiment, as shown in FIG. 1, an ultrasonicirradiator 3 a comprises a plurality of ultrasonic transducers 1 a and 1b installed on one surface of a sheet member 2. In the case where thesheet member 2 is sound-conductive, the ultrasonic transducers 1 a and 1b can be appropriately arranged on any of inside and/or outside planesof the sheet member 2.

The ultrasonic transducers 1 a and 1 b may be ones having a drivingelectrode arranged on one plane of a piezoelectric element composed ofceramics (e.g., PZT (Pb(Zr*Ti₃)O₃), etc.) and an opposed groundelectrode arranged on the other plane of the piezoelectric element. Theultrasonic transducers 1 a and 1 b output ultrasonic waves by applying adrive voltage of a predetermined frequency between the driving electrodeand the opposed ground electrode. The ultrasonic transducers 1 a and 1 bcan be a composed one of mutually adhered two piezoelectric elements ina pair, by placing each driving electrode in contact between opposedground electrodes at both outer sides. In this embodiment, each group ofultrasonic transducers 1 a and 1 b is connected via conductors 4 a and 4b to respective different drive systems, and for example, can be turnedon or off at a mutually inverse timing. Of course, the device can bedriven by keeping all of them in a same condition, without beingseparated into respectively different groups such as 1 a or 1 b.

The sheet member 2 is preferably made of a material that is flexibleand/or elastic, and which can be formed by several types of rubber sheetmembers, foamed rubber sheet members such as expanded butylene orexpanded silicon, fabrics or unwoven textiles, etc. Because the sheetmember 2 has flexibility and elasticity, each position of the ultrasonictransducers 1 a and 1 b can be adaptively changed to fit to athree-dimensionally curved living body surface, such as the abdominalregion, the thigh, the buttocks, the chin and so on. The ultrasonictransducers 1 a and 1 b are normally installed on the sheet member whilebeing set slightly apart by a thickness of the transducer, so that theopposed ground electrode side can contact the living body surface.

The ultrasonic irradiator 3 a further comprises a joining member 5composed of a pair of plane fasteners 5 a and 5 b (e.g., Magic Tapemanufactured by KURARAY CO., LTD. [Trademark]) at the periphery of theultrasonic irradiator 3 a, and a plurality of ultrasonic irradiators 3 aare arranged to be joined together via the joining member 5.

In the ultrasonic irradiator 3 a, it is preferable to arrange an airback layer, such as a material containing air foam or an air layer, onthe back side of the assembly made up of the sheet member 2 and theultrasonic transducers 1 a and 1 b, so as to reflect, by means of theair foam or air layer, the radiation of ultrasonic waves coming from theultrasonic transducers 1 a and 1 b toward the living body side contactsheet member 2. Thereby, all of the ultrasonic energy is output fromeach of the ultrasonic transducers 1 a and 1 b toward the front livingbody contact side of the sheet member 2 assembly and an output plane isformed at the front side. In this case, the resonance frequencycharacteristic of the ultrasonic transducers 1 a and 1 b acquires asharp narrow band. However, a narrow band is sufficient in the casewhere the ultrasonic transducers 1 a and 1 b irradiate continuous waves(CW).

However, in the case where the ultrasonic transducers 1 a and 1 birradiate pulse waves, it is necessary for the spectrum to be of a broadband, by arranging a sonic absorbing layer (e.g., a rubber containing ametal powder, etc.) on the back side of the sheet member 2 and/or theultrasonic transducers 1 a and 1 b. The air back layer or the sonicabsorber layer may be laminated onto the back side of the assembly madeup of the sheet member 2 and the ultrasonic transducers 1 a and 1 b.Alternatively, the sheet member 2 may be arranged so as to function asthe air back layer by including air foams therein, or to function as thesonic absorber layer by including metallic powders therein. The frontside of ultrasonic irradiator 3 a can have an impedance layeracoustically matched with the living body, an insulation layer and aground electrode layer, etc., formed in the irradiator on the side ofthe living body.

It is preferable that an insulation layer and/or a conductive layer befurther arranged on the front side of the assembly made up of the sheetmember 2 and the ultrasonic transducers 1 a and 1 b, by laminating suchlayers on the electrode or by lapping them at a certain distance.Thereby, it is possible to avoid an electric current from leaking to theliving body, or for unnecessary electromagnetic radiation to be radiatedoutwards, because the conductive layer can be connected to a groundelectric potential. The conductive layer may be arranged by using aprocess for adding conductivity to the back surface of the sheet member2, or by laminating an aluminum fiber fabric onto the back side of thesheet member 2 assembly.

In the case where the sheet member 2 is composed of several types ofhard rubber sheet material, the sheet member 2 may possess onlyflexibility without elasticity. In this case, it is preferable toarrange a plurality of linear recesses 2 a (as indicated by hypotheticallines) on the surface of the sheet member 2, as depicted in FIG. 1. Byproviding the linear recesses 2 a in the sheet member 2, when the sheetmember 2 is deformed along the linear recesses 2 a, the opening of thelinear recesses 2 a is changed into a ship shape by causing the upperedges of the linear recesses 2 a to move apart, and the sheet member 2also becomes easily deformable in a direction transverse to the linearrecesses 2 a.

The linear recesses 2 a are arranged between the ultrasonic transducers1 a and 1 b and need not necessary be straight lines. Further, it is notnecessary that the linear recesses 2 a be mutually parallel. Further,the width of the linear recesses 2 a may be freely determined. Thelinear recesses 2 a are arranged from one surface toward the othersurface in the sheet member, and may or may not penetrate through to theother surface.

Next, it shall be explained, by referring to FIG. 1 and FIG. 2, how touse the ultrasonic irradiation apparatus according to the aboveembodiment.

In one exemplary usage, the ultrasonic irradiator 3 a is shown crosssectionally in FIG. 2 corresponding to a portion of the cross sectionII-II shown in FIG. 1, wherein the ultrasonic transducers 1 a and 1 bare arranged to fit along a three-dimensionally curved surface of aliving body 6 such as the abdominal region, the thigh, the buttocks, thechin, and so on. Then, the ultrasonic irradiator 3 a is joined to anadjacent ultrasonic irradiator 3 a with a joining member 5 composed of apair of plane fasteners 5 a and 5 b, and a fluidic material layer 7,serving as an ultrasonic conducting medium, is provided between theliving body 6 and the ultrasonic irradiator 3 a.

The fluidic material layer 7 functions as an acoustic coupling mediumfor eliminating air between the ultrasonic transducers 1 a and 1 b andthe living body 6, as well as for securing an acoustic coupling betweenthe ultrasonic transducers 1 a and 1 b and the living body 6. A materialfor the fluidic material layer 7 is, e.g., acoustic jelly.

In the case where the ultrasonic irradiation apparatus irradiates ahuman with ultrasonic waves, it is required to wash and disinfect theultrasonic irradiator 3 a every time it is used, and so on. Therefore,when jelly is used as the fluidic material layer 7, the jelly ispreferably water-soluble. The sheet member 2 is preferably waterproofand tolerant to disinfectants.

In the present ultrasonic irradiation apparatus, it is possible tointerpose a soft material layer, such as a gel material like agar, inplace of the fluidic material layer 7, and further to interpose similaror other materials along with the sound conducting sheet member 2. Forexample, a hygroscopic polymer, containing a large amount of water,etc., is applicable as the gel material like agar, and a non-foamcontaining rubber or the like is applicable as the sound conductivesheet member 2.

Further, the fluidic material layer 7, or the material substitutedtherefor, preferably is formed of a heatable or refrigeratable highspecific heat material (hot pack or cold pack), whereby it is possibleto enhance the effectiveness of the irradiation with ultrasonic waves tothe living body 6 by controlling the temperature of the fluidic materiallayer 7, or the substituted material, by heating or cooling thereof inadvance. In the case of irradiating a human with ultrasonic waves, thetactile feeling of the object can be improved by using the fluidicmaterial layer 7, or the substituted material, which has been heated orcooled.

In the ultrasonic irradiation apparatus, fats in the living body 6 aredecomposed (lipolysis) by irradiation with ultrasonic waves (e.g. 500kHz at 110 mW/cm²). Then, when sonic fields of ultrasonic waves from theultrasonic transducers overlap within the living body 6, due to mutualinterference, some parts having added pressure amplitudes and otherparts having reduced pressure amplitudes are generated. Thus, in suchoverlapping portions of the pressure amplitude, the irradiation dose ofultrasonic waves may be excessive or insufficient.

When the irradiation dose of ultrasonic waves becomes excessive atcertain portions in the living body, heat may be generated or tissuesmay become injured in such portions. Therefore, the Thermal Index (TIS)and the Mechanical Index (MI) have been introduced as a measure of theirradiation dose of ultrasonic waves to the living body by Food and DrugAdministration (FDA) of the United States of America (U.S.A.). Accordingto FDA publications, a safe range for irradiation values to the livingbody is TIS=2 and MI=0.3.

TIS is a numerical value for soft tissues in the Thermal Index, whereinTIS=2 means that the temperature of the soft tissues is raised 2° C.during continuous irradiation of ultrasonic waves. For a living body at36° C., this implies a temperature of 38° C. This temperature is oftenencountered in catching a cold and is positively safe to the livingbody.

On the other hand, the Mechanical Index indicates a degree where tissuesare injured by cavitation. MI=0.3 is a safe level to any mammal.

When the ultrasonic irradiation apparatus irradiates with ultrasonicwaves of 500 kHz at 110 mW/cm², as mentioned above for lipolysis in theliving body 6, even if the strength of ultrasonic waves becomes 800mW/cm² due to overlapping of the ultrasonic waves, it is still within asafe range because TIS remains 2 or below and MI remains 0.3 or below.Normally, upon overlapping of two ultrasonic transducers, the ultrasonicwave strength never exceeds being doubled, i.e., 220 mW/cm² or more.But, during other uses, the overlapping of the ultrasonic transducers 1a and 1 b should not be ignored.

Therefore, in the ultrasonic irradiation apparatus, the ultrasonictransducers 1 a and 1 b are each driven respectively by different drivesystems, which are arranged in a cross-stripes pattern. Thereby, each ofultrasonic transducers 1 a and 1 b is arranged to avoid unnecessaryoverlapping of the sonic fields of the ultrasonic transducers 1 a and 1b, so that each ultrasonic transducer 1 b is in the center of eachrhombus making up a system (or group) of the ultrasonic transducers 1 a.Further, each of the ultrasonic transducers 1 a is in the center of eachrhombus making up a system (or group) of the ultrasonic transducers 1 b.

In the ultrasonic irradiation apparatus, it is possible to drive each ofthe ultrasonic transducers 1 a and 1 b via each of conductors 4 a and 4b which are respectively connected to different driving systems, byturning them ON/OFF at a mutually inverse timing. Thereby, overlappingof the sonic fields in the ultrasonic transducers 1 a and 1 b is nevergenerated.

To avoid that the irradiation dose of ultrasonic waves becomes excessiveor insufficient due to overlapping of the sonic fields of the ultrasonictransducers 1 a and 1 b, an example of driving the ultrasonictransducers 1 a and 1 b by turning them ON/OFF at a mutually inversetiming has been discussed. However, as an alternative, while constantlydriving one of the ultrasonic transducers 1 a or 1 b at a fixed timing,the other one can be driven via a phase-shifted circuit, which iscontinuously changed in phase, or can be driven by continuously andslightly changing its frequency. Thereby, the added and reduced portionsof the pressure amplitudes due to interference are continuously keptmoving in the living body 6, so that the irradiation dose of ultrasonicwaves is averaged within the region irradiated by the ultrasonic waves.Therefore, it is possible to keep the irradiation dose of ultrasonicwaves from becoming either excessive or insufficient. It is alsopossible to make the distribution of the output strength (mW/cm²)uniform at the irradiation output plane, or to make the distributionshape like a plateau or mountain, by weakening the edge portion of thedistribution and strengthening the center portion of the distribution.

Adjusting the output allocation for each of the ultrasonic transducers 1a and 1 b may also be used in place of the method of changing thedriving means of the ultrasonic transducers 1 a and 1 b.

As one method for adjusting the output allocation of each of theultrasonic transducers 1 a and 1 b, it is applicable to connect atransformer for impedance conversion in parallel to the unit where eachof the ultrasonic transducers 1 a and 1 b, or a plurality of ultrasonictransducers 1 a and 1 b, are connected in series or in parallel.Thereby, the ultrasonic transducer unit is connected to the secondaryside of the transformer and a driving power source is connected to theprimary side of the transformer. In the case of using a transformer forimpedance conversion, it is possible to set the output allocation foreach of the ultrasonic transducers or the unit at any ratio, by changinga turn ratio or coupling coefficient of the transformer (e.g., bychanging the insertion degree of a magnetic core).

By connecting an inductance in series to each of the ultrasonictransducers, which is approximately resonant to each of the ultrasonictransducers 1 a and 1 b, or by connecting an inductance in series, whichis approximate resonant to a unit made up from a plurality of ultrasonictransducers connected in series or parallel, it is also possible toadjust the output allocation of each ultrasonic transducer or that ofthe unit. It is also possible to achieve an effect of reducing aninvalid electric power by arranging the inductance. The inductance issmaller in size than that of the transformer for impedance conversion,and can be installed for each of the ultrasonic transducers 1 a and 1 bor for the unit overall.

The arrangement of ultrasonic transducers 1 a and 1 b is not limited tothe cross-stripes pattern arrangement depicted in FIG. 1, and may be anyother arrangement, e.g., a hexagonal close-packed structure or the like.Also, the shape of each of the ultrasonic transducers 1 a and 1 b is notlimited to a round shape, as depicted in FIG. 1 and can be freelydesigned in, e.g., square, rectangular or other patterns.

Next, referring to FIG. 3, another method for using the ultrasonicirradiation apparatus according to this embodiment shall be explained.

In the method described in FIG. 3, the ultrasonic irradiator 3 a isarranged so as to make contact with the living body 6 via the fluidicmaterial layer 7 under the surface of a side of the sheet member 2opposite to the ultrasonic transducers 1 a and 1 b. In this case,ultrasonic waves from the ultrasonic transducers 1 a and 1 b are outputthrough the sheet member 2 and transferred to the living body 6 throughthe fluidic material layer 7. Therefore, the sheet member 2 should besound-conductive, and be composed of a material that does not containsubstances which would reflect, and/or absorb ultrasonic waves, such asfoam, gas or metal powder. For example, the material can be selectedfrom among several types of rubber sheets such as, e.g., natural rubber,synthetic rubber or silicon rubber, etc. Materials containing substanceswhich reflect and/or absorb ultrasonic waves, such as foamed rubber,foamed plastic, fabrics or textiles, etc., are not applicable in thissituation.

It is preferable to arrange an air back layer 8 and an electromagneticshielding layer 9 on the opposite upper surface of the ultrasonictransducers 1 a and 1 b on the sheet member 2, and to arrange aprotective layer 10 covering the ultrasonic transducers 1 a and 1 b, theair back layer 8 and the electromagnetic shielding layer 9. Theprotective layer 10 is bonded to the sheet member 2 at a peripheralportion thereof and forms a bag-like construction. Further, theprotective layer 10 contains the ultrasonic transducers 1 a and 1 b, theair back layer 8 and the electromagnetic shielding layer 9 in the backarea between the sheet member 2 and itself. In this case, a joiningmember 5 (a pair of plane fasteners 5 a and 5 b) for joining theultrasonic irradiator 3 a is arranged at the peripheral portion of theprotective layer 10.

The air back layer 8 can be made of a flexible sheet member composed ofa foamed material such as foamed polyethylene or foamed rubber, etc.Further, the electromagnetic shielding layer 9 can be a flexible sheetmember composed of a metal foil, a metal mesh or a conductive rubber,etc. In the ultrasonic irradiation apparatus depicted in FIG. 3, aplurality of electromagnetic shielding layers 9 are arranged overlappingeach other so that each of them can freely slide.

As the protective layer 10, several types of rubber sheet members,foamed rubber sheet members, such as expanded butylene or expandedsilicon, fabrics or unwoven textiles, etc., may be applicable. Theprotective layer 10 is preferably waterproof for improving disinfection.It is not necessary to fill any special material on the inside of theprotective layer 10, and only air is sufficient. The air back layer 8may also simply be an air layer, wherein air existing on the inside ofthe protective layer 10 may be used in place of the air back layer 8.

In the ultrasonic irradiation apparatus depicted in FIG. 3, because theultrasonic irradiator 3 a contacts with the living body 6 via a surfaceof the sheet member opposite to the ultrasonic transducers 1 a and 1 b,the ultrasonic irradiator 3 a can smoothly slide along thethree-dimensionally curved surfaces of the living body 6, and in thecase of irradiating a human with ultrasonic waves, the contact feelingof the object can be improved. Because the ultrasonic transducers 1 aand 1 b are arranged on the sheet member 2, on a side opposite to theliving body 6, the sheet member is also effective for protecting theultrasonic transducers 1 a and 1 b.

Next, an ultrasonic irradiation apparatus according to a secondembodiment of the present invention shall be explained with reference toFIG. 4 through FIG. 7.

In the ultrasonic irradiation apparatus, an ultrasonic irradiator 3 b iscomposed of a plurality of ultrasonic transducers 1 a and 1 b installedon a net member 11 and arranged in a plane, as described in FIG. 4. Thenet member 11 is preferably composed of a material having flexibilityand elasticity, wherein the net member 11 is formed of at least one typeof material such as a string, a band, a spring, a chain and linked rodsthat are freely rotatable, and being fastened by knots 12. Theultrasonic transducers 1 a and 1 b are arranged in a checkered patternwithin the net member 11 and are adhered to the net member 11. However,the arrangement of the ultrasonic transducers 1 a and 1 b is not limitedto such a checkered pattern.

The strings for forming the net member 11 may be, for example, asynthetic resin string, a rubber line (a rubber string) or a plasticfilament, etc. In the event a band is used, the band for forming the netmember 11 may be composed of, for example, plastic, rubber, textile,fabric, very thin metal foil, a spring or a chain, etc. The net member11 may be composed of two longitudinal strings 13 and two lateralstrings 14, as depicted in FIG. 5. The longitudinal string 13 and thelateral string 14 may be mutually knotted or bonded at an intersection15. In this case, the ultrasonic transducers 1 a and 1 b may be adheredat their sides to the longitudinal string 13 and the lateral string 14,or it may be applicable to form a surrounding groove along a side planeof the transducer (although not indicated in the figure), and to arrangethe ultrasonic transducers 1 a and 1 b so as to be constrained bybinding the longitudinal string 13 and the lateral string 14 to such agroove.

In FIG. 5, the longitudinal string 13 is shown by a dotted line and thelateral string 14 is shown by a solid line, in order to make therelationship between the longitudinal string 13 and the lateral string14 clear. Also, the longitudinal string 13 and the lateral string 14 aredepicted in the figure as shown apart from the ultrasonic transducers 1a and 1 b, to better show the existence of the longitudinal strings 13and the lateral strings 14.

Further, in the ultrasonic irradiator 3 b, as shown in FIG. 6, theultrasonic transducers 1 a and 1 b may be installed on a plurality ofbands 16. The plurality of bands 16 are mutually connected by, e.g., astring (not shown), so that the ultrasonic transducers 1 a and 1 b arearranged in a hexagonal close-packed structure to thereby form the netmember 11.

In the ultrasonic irradiator 3 b as shown in FIG. 7, each of theultrasonic transducers 1 a and 1 b may be connected by two strings 17,wherein the two strings 17 are mutually connected by, e.g., anotherstring (not shown), so that the ultrasonic transducers 1 a and 1 b arearranged in a hexagonal close-packed structure to thereby form the netmember 11. The arrangement of the ultrasonic transducers 1 a and 1 b isnot limited to a hexagonal close-packed structure.

In this case, the ultrasonic transducers 1 a and 1 b have a surroundinggroove 18 on the side and are constrained by the strings 17, which areappropriately positioned. The two strings 17 are banded together bycenter holes of spacers 19, which are arranged between the ultrasonictransducers 1 a and 1 a, or ultrasonic transducers 1 b and 1 b.

In the ultrasonic irradiator 3 b shown in FIG. 7, it may be applicableto use, e.g., thin bands or thin springs in place of the strings 17.

The ultrasonic irradiators 3 b shown in FIG. 4 through FIG. 7 may havethe same structure as the ultrasonic irradiator 3 a, except that theultrasonic transducers 1 a and 1 b are installed on the net member 11.

Next, referring to FIG. 8 through FIG. 10, an ultrasonic irradiationapparatus according to a third embodiment of the present invention shallbe explained.

In the ultrasonic irradiation apparatus of this embodiment, a pluralityof ultrasonic transducers 1 a and 1 b, composed of a driving electrode22 formed on one plane of a flexible piezoelectric sheet member 21 andan opposed ground electrode 23 formed on the other plane of the flexiblepiezoelectric sheet member 21, are arranged in a plane facing eachother, for forming the ultrasonic irradiator 3 c as depicted in FIG. 8.In the ultrasonic irradiator 3 c, the ultrasonic transducers 1 a and theultrasonic transducers 1 b are alternately arranged in each row of atessellate arrangement (cross-stripes pattern).

As the flexible piezoelectric member 21, a sheet of an organicpiezoelectric material, like PVDF, or a sheet formed under an electricfield from a plastic containing fine-grained piezoelectric ceramic, suchas PZT, may be used. The driving electrode 22 and the opposed groundelectrode 23 may be formed by a metal vapor deposition method on asurface of the flexible piezoelectric member 21.

The flexible piezoelectric member 21, when composed of the materialsmentioned above, generally has flexibility, but is not sufficient inelasticity. Therefore, the flexible piezoelectric member 21 preferablyhas a plurality of linear recesses 24 on its surface. In the ultrasonicirradiator 3 c depicted in FIG. 8, the linear recesses 24 are arrangedin a straight pattern between the ultrasonic transducers 1 a and 1 b,and the plurality of linear recesses 24 are formed to be mutuallyparallel. Further, the linear recesses 24 are formed from one surface ofthe flexible piezoelectric member 21 toward the other surface, so as topenetrate the flexible piezoelectric member 21 in a thickness directionthereof.

Because the flexible piezoelectric member 21 includes linear recesses 24in the ultrasonic irradiator 3 c, when deformed along the linearrecesses 24, the opening portions of the linear recesses 24 can bedeformed into a ship shape, as a result of the upper edges of the linearrecesses 24 moving apart, and it can also be easily deformed in adirection transverse to the linear recesses 24. Thereby, the positionsof the ultrasonic transducers 1 a and 1 b, provided in the ultrasonicirradiator 3 c, are mutually and flexibly deformablethree-dimensionally.

The linear recesses 24 can be arranged between the ultrasonictransducers 1 a and 1 b, but are not limited to being in a linear shape,and need not necessarily be mutually in parallel. Moreover, they may befreely arranged, for example, the ultrasonic transducers 1 a and 1 b canbe arranged in a hexagonal close-packed structure, wherein the shape ofthe linear recesses 24 can be a curved waveform line winding between theultrasonic transducers 1 a and 1 b. Further, the linear recesses 24should be formed from one surface of the flexible piezoelectric member21 toward the other surface, and can be non-penetrating with respect tothe flexible piezoelectric member 21. In the case that they do notpenetrate the flexible piezoelectric member 21, the linear recesses 24may be arranged alternately on one surface and the other surface of theflexible piezoelectric member 21.

Further, when the linear recesses 24 in FIG. 8 are formed by penetratingthe flexible piezoelectric member 21 from one surface to the othersurface, a portion of the linear recesses 24 should not reach to aperipheral edge, so as not to divide the flexible piezoelectric member21 into pieces. However, in the case where the linear recesses 24 do notpenetrate through the thickness of the flexible piezoelectric member 21,the linear recesses 24 may be arranged over the flexible piezoelectricmember 21 from one peripheral edge to the opposed peripheral edge.

The ultrasonic irradiator 3 c shown in FIG. 8 can have the samestructure as the ultrasonic irradiator 3 a, except that the ultrasonictransducers 1 a and 1 b are formed from the flexible piezoelectricmember 21.

Next, referring to FIG. 9 and FIG. 10, a method for using the ultrasonicirradiation apparatus shall be explained.

The ultrasonic irradiator 3 c shown in FIG. 9 corresponds to the crosssection IX-IX of FIG. 8, whereas the ultrasonic irradiator 3 c shown inFIG. 10 corresponds to the cross section X-X of FIG. 8. The ultrasonictransducers 1 a and 1 b are actually composed of the driving electrode22 and the opposed electrode 23, and are arranged facing each otheractually on both planes of the flexible piezoelectric member 21, asdepicted in FIG. 8. However, for convenience of illustration, they areshown in FIG. 9 and FIG. 10 as if the ultrasonic transducers werearranged on one plane only of the flexible piezoelectric member 21,similar to the arrangement of FIG. 1.

In the ultrasonic irradiation apparatus of the present embodiment, theultrasonic irradiator 3 c is deformable in a direction along the linearrecesses 24 as depicted in FIG. 9 as a result of the flexibility of theflexible piezoelectric member 24. The ultrasonic irradiator 3 c is alsodeformable in a direction transverse to the linear recesses 24, asdepicted in FIG. 10, because the opening portions of the linear recesses24 can be changed into a ship shape by the upper edges of the linearrecesses 24 moving apart.

Thereby, the ultrasonic irradiator 3 c can be deformablethree-dimensionally, as depicted in FIG. 9 and FIG. 10, and theultrasonic transducers 1 a and 1 b are fitted along thethree-dimensional curved surfaces of the living body 6 such as theabdominal region, the thigh, the buttocks, the chin and so on. Then, afluidic material layer 7, namely an ultrasonic conducting medium, is tobe placed between the living body 6 and the ultrasonic irradiator 3 c.

The ultrasonic irradiator 3 c irradiates with ultrasonic waves, in themanner indicated in FIG. 9 and FIG. 10, and thereby induces lipolysiswithin the living body 6 or performs other processes.

The ultrasonic irradiator 3 c may have a reinforcement material layer 25on the side opposed to the living body 6 in the flexible piezoelectricmember 21. The reinforcement material layer 25 may be composed of aflexible electric shielding material, containing foams, or an air backlayer for reflecting ultrasonic waves may also be used as thereinforcement material layer 25.

The reinforcement material layer 25 prevents leakage of electric currentto the living body, or prevents unnecessary external electromagneticradiation, when a conductive layer is further formed on a surfaceopposed to the flexible piezoelectric member 21 and the conductive layeris kept at a ground electric potential. The reinforcement material layer25 may further include a protective layer, composed of flexible andelastic foamed rubber, on the outside thereof.

The ultrasonic irradiator 3 c may further have a protective layer (notshown), which is a living body contact sheet, provided between thesurface opposed to the reinforcement material layer of the flexiblepiezoelectric member and the surface of the living body 6. When theliving body contact sheet is formed on the side of the living body 6, itis composed of a sound-conducting material, such as a rubber sheet whichis flexible and/or elastic and does not contain foams therein, so thatultrasonic waves are able to pass therethrough. The protective layerpreferably is attached with, e.g., epoxy adhesives, so as not to containair between the flexible piezoelectric member 21 and itself, at leastwithin areas where it is in contact with the ultrasonic transducers 1 aand 1 b. in order to transmit ultrasonic waves successfully.

In each of the ultrasonic irradiators 3 a, 3 b and 3 c, the ultrasonictransducers 1 a and 1 b may be arranged in a cross-stripes or checkeredpattern, as depicted in FIG. 1, FIG. 4 and FIG. 5, or may be arranged ina hexagonal close-packed structure, as depicted in FIG. 6 and FIG. 7.Further, in the tessellate (cross-stripes) arrangement, as depicted inFIG. 8, the ultrasonic transducers 1 a and the ultrasonic transducers 1b may be alternately arranged in each row of the tessellate arrangement.

This is preferable because, while moving the ultrasonic irradiator alongsurfaces of the living body 6, a trajectory of the ultrasonictransducers 1 a and a trajectory of the ultrasonic transducers 1 b areoverlapped irrespective of the driving direction, and thereby it ispossible to eliminate a portion where the living body 6 is notirradiated with ultrasonic waves, based on arranging the ultrasonictransducers 1 a and 1 b in a hexagonal close-packed structure, asdepicted in FIG. 6 and FIG. 7.

In each of the figures, the ultrasonic transducers 1 a and 1 b are shownas circles in plan view, but they are not limited to circles and may beof any shape. In the ultrasonic irradiator 3 c depicted in FIG. 8, theultrasonic transducers 1 a and 1 b can be easily formed in any shape,because the driving electrode 22 and the opposed electrode 23 formingthe ultrasonic transducers 1 a and 1 b are formed on the surface of theflexible piezoelectric member 21 by means of a metal vapor depositionmethod.

Next, referring to FIG. 11 and FIG. 12, an ultrasonic irradiationapparatus according to the fourth embodiment of the present inventionshall be explained.

In the ultrasonic irradiation apparatus, the ultrasonic irradiator 3 ais installed on a surface of a flexible planar bag 31 containing afluidic material layer 7, as depicted in FIG. 11. The planar sheet (bag)31 is composed of a soft material having both flexibility andelasticity, and contains a fluidic material 32 as an ultrasonicconducting medium.

The ultrasonic irradiation apparatus is placed in contact with anobject, such as a living body 6, via the fluidic material layer 7 on thesurface of the planar bag 31, and irradiates the object with ultrasonicwaves via the planar bag by the ultrasonic irradiator 3 a.

Then, in the ultrasonic irradiation apparatus, it is possible to changethe thickness of the planar bag 31 containing the fluidic material 32,as well as to change the relative position between the object and theultrasonic transducers 1 a and 1 b installed in the ultrasonicirradiator 3 a. Thereby, the overlapping positions of the irradiatedultrasonic waves within the object may be changed and an excess orinsufficient irradiation dose of ultrasonic waves at a specific area ofthe object can be avoided.

Further, the planar bag 31 can be removed from the ultrasonic irradiator3 a and can be heated using a microwave oven or can be cooled using anelectric refrigerator.

Because the planar bag 31 is flexible and contains the fluidic material32, the thickness or shape of the planar bag 31 can be changed. However,it is preferable that the planar bag 31 has a tube 33 at a side planethereof, for channeling the inside and outside, wherein the tube 33 isconnected to a pump (not shown). Thereby, the pump can supply thefluidic material 32 to the planar bag 31 through the tube 33 ordischarge the fluidic material 32 from the planar bag 31, and thethickness or shape of the planar bag 31 can be changed in a timesequence, by changing an amount of the fluidic material 32 contained inthe planar bag 31. The meaning of “changed in a time sequence” includeschanging at any time-range, or randomly, and is not limited to changingat a predetermined time period exactly.

In the planar bag 31, a partial deviation of the fluidic material 32 iscaused inside the planar bag 31, namely, a partial amount of the fluidicmaterial 32 within the planar bag 31 is excessively increased, beingaffected by supplying or discharging the fluidic material 32 by a pumpor though the function of the gravity, etc., wherein the distancebetween the object and the ultrasonic transducers 1 a and 1 b installedin the ultrasonic irradiator 3 a may be partially varied to become longor short. Further, when the ultrasonic irradiator 3 a and the planar bag31 are applied to a vertical surface of the living body 6, the fluidicmaterial 32 is gathered at a lower portion. As a result, the lowerportion is expanded, the upper portion is narrowed, the surface ofultrasonic irradiator 3 a is greatly inclined, and it is difficult tocontact curved surfaces of the living body 6. As the remedy, the planarbag 31 has a connection member 34, connecting an upper plane and abottom plane within the planar bag 31, for keeping the thickness of theplanar bag 31 within a predetermined range.

The connection member 34 is composed of a cylindrical member 35installed on an inner wall 31 a of the bottom plane in the planar bag 31and a cylindrical member 36 installed on an inner wall 31 b of the upperplane in the planar bag 31, wherein the cylindrical member 36 isinserted inside cylindrical member 35, so as to slide along an innerwall of the cylindrical member 35, as depicted in the enlarged view ofFIG. 12. The cylindrical member 36 has a claw member 37 on a side planethereof, and includes a wide slit (not shown) in an axial direction ofthe cylinder. The member 36 having the claw 37 is inserted into thecylindrical member 35 from the upper side by elastic deformation of thecylindrical member 36, and the claw 37 is restored and inserted in anopening 38 provided in a side wall of the cylinder 35. Then, the clawmember becomes slidingly engaged with the cylinder 35. Sliding of theclaw member 37 is limited at an upper end 38 a of the opening 38, andthereby the thickness of the planar bag 31 is maintained within apredetermined range.

In the ultrasonic irradiation apparatus, the fluidic material 32contained in the planar bag 31 may be a heatable or refrigeratable highspecific heat material. In the case where the fluidic material 32 is ahigh specific heat material, the planar bag 31 may be detached and thefluidic material 32 in the detached planar bag 31 can be heated by,e.g., a microwave oven or cooled by, e.g., an electric refrigerator. Itis possible to improve the effectiveness of ultrasonic irradiation tothe object by irradiating the living body surface at a high temperatureor a low temperature. Further, in the case where the object is a human,the tactile feeling of the person being irradiated can be improved byheating or cooling the fluidic material 32, as has been described above.

For example, a mixture of water, propylene glycol and methylcellulosemay be applicable as the heatable fluidic material 32. For example, amixture of water, hygroscopic polymer and polyhydric alcohol may beapplicable as the refrigeratable fluidic material 32.

In the ultrasonic irradiation apparatus, the ultrasonic irradiator 3 ais installed on the surface of the flexible planar bag 31 containing thefluidic material layer 7, and can be freely installed or detached, asdepicted in FIG. 11. However, the ultrasonic irradiator 3 a may also beintegrated together with the surface of the planar bag 31 as a singleunit. In this case, it should be arranged so that air can never existbetween the planar bag 31 and the ultrasonic transducers 1 a and 1 b.

In the ultrasonic irradiation apparatus, the thickness of the planar bag31 is kept within a predetermined range by the connection member 34composed of the cylindrical members 35 and 36, as shown in FIG. 12.However, alternatively, it is possible to tie the upper plane and thebottom plane at the corresponding position within a predetermineddistance in the planar bag 31 using, e.g., flexible strips or stringmembers.

In the ultrasonic irradiation apparatus, any one of the ultrasonicirradiators 3 b shown in FIG. 4 through FIG. 7, or the ultrasonicirradiator 3 c shown in FIG. 8, may be used instead of the ultrasonicirradiator 3 a.

Next, referring to FIG. 13 through FIG. 19, an ultrasonic irradiationapparatus according to a fifth embodiment of the present invention shallbe explained.

In the ultrasonic irradiation apparatus, the ultrasonic irradiator 3 ais arranged inside of a flexible planar bag 41. One plane of theflexible planar bag 41 is composed of a rigid member 42, and the otheropposed plane is composed of a soft material 43 having flexibility andelasticity, which serves as an acoustic window. Further, the planar bag41 contains a fluidic material 44 as an ultrasonic conductive medium.The ultrasonic irradiator 3 a is arranged so as to be freely moved inparallel along a plane area 42 a of the rigid material 42, or to befreely tilted in reference to the plane area 42 a, as indicated by thearrows in FIG. 13.

In the ultrasonic irradiation apparatus, the planar bag 41 is in contactwith the living body 6, via the fluidic material layer 7, at the outputwindow composed of the soft material 43. Namely, at least one plane ofthe ultrasonic irradiator 3 a (the plane of the soft material 43 in thepresent embodiment) irradiates an object with ultrasonic waves via theflexible planar bag 41. Because one plane of the planar bag 41 iscomposed of a rigid material 42, the bag is easily handled by holdingthe side of the rigid material 42.

Because the ultrasonic irradiator 3 a is arranged so as to be freelymoved along the plane area 42 a of the rigid material 42, or to befreely tilted with respect to the plane area 42 a, in the ultrasonicirradiation apparatus, the relative position between the object and theultrasonic transducers 1 a and 1 b can be changed. Therefore, anoverlapping portion of the ultrasonic waves from the ultrasonictransducers 1 a and 1 b with respect to the object is varied inside ofthe object, and an excessive or insufficient irradiation dose ofultrasonic waves at a specific area of the object can be avoided.

Further, because the ultrasonic irradiator 3 a is arranged so as to befreely moved along the plane area 42 a of the rigid material 42, or tobe freely tilted with respect to the plane area 42 a, in the ultrasonicirradiation apparatus, unevenness of the sonic field caused by an unevenarrangement of the ultrasonic transducers 1 a and 1 b is averaged.Therefore, a displacement range of movement or tilting of the ultrasonicirradiator 3 a is preferably of about the same distance as an intervalbetween the ultrasonic transducers 1 a and 1 b.

In the ultrasonic irradiation apparatus, a soft material 43 is arrangedalong one plane of the planar bag 41. The ultrasonic irradiationapparatus can make contact, via the soft material 43, with an objecthaving three-dimensionally curved surfaces such as the living body 6.Therefore, the ultrasonic irradiator can be arranged inside of theplanar bag 41 so that the plurality of ultrasonic transducers isinstalled on a surface of the rigid sheet, as shown by 3 a in FIG. 13.

Next, a structure by which the ultrasonic irradiator 3 a is freelymovable along the plane area 42 a of the rigid material 42, or is freelytilted with respect to the planar area 42 a, shall be explained.

In the case where the ultrasonic irradiator 3 a is arranged so as to befreely moved along the planar area 42 a of the rigid material 42, theultrasonic irradiator 3 a is suspended from the rigid material 42 by atleast three support members 45, so as to be flexibly movable, as shownin FIG. 14.

Then, one support member 45 is connected, via a watertight bearing 46,to the rotating axis of a motor (not shown) which is arranged outside ofthe planar bag 41, so as to be freely rotated. A disc 47 is installed atan end of the support member 45, and a pin 48, which is arranged at theperipheral portion so as to be project vertically downward, is insertedinto a long narrow opening 49 a provided in the ultrasonic irradiator 3a. The opening 49 a has a length corresponding to a diameter of the disc47.

As a result of this structure, because the pin 48 engages with theopening 49 a and moves the ultrasonic irradiator 3 a in accordance withrotation of the support member 45, the ultrasonic irradiator 3 a isfreely moved along the planar area 42 a of the rigid material 42.

In this case, a guide member 50 may be arranged at a right-hand locationinside of the rigid material 42, for supporting an edge portion of theultrasonic irradiator 3 a, in a direction crossing at a right angle withrespect to the length direction of the opening 49 a. When a guide member50 is provided also at the other left-hand side of the rigid material42, the ultrasonic irradiator 3 a reciprocates in a direction crossingat a right angle to the length direction of the opening 49 a becausemovement in the length direction of the opening 49 a is restricted bythe guide member 50.

Further, an insertion hole 49 b into which the pin 48 is inserted may beprovided as shown in FIG. 15, in place of the long narrow opening 49 a.In this case, because the pin 48 is engaged in the insertion hole 49 band, in accordance with rotation of the support member 45 a, is drivento move the ultrasonic irradiator 3 a, the ultrasonic irradiator 3 aundergoes a circular motion along the periphery of the disc 47.

Next, a case in which the ultrasonic irradiator 3 a is arranged so as tobe freely tilted with respect to the planar area 42 a of the rigidmaterial 42 shall be explained. The ultrasonic irradiator 3 a issupported approximately at the center of a side wall of the rigidmaterial 42 by a freely rotatable support member 51, as depicted in FIG.16.

On the right-hand side wall of the rigid material 42, a rotating axle 52is installed and connected, via a watertight bearing (not shown) to amotor (also not shown) which is arranged on the outside of the planarbag 41. A disc 53 is installed at one end of the rotating axix 52, and apin 54, arranged at the peripheral edge portion of the disc 53 andprojecting frontward, is inserted into a long narrow slit 55 arranged ina side plane of the ultrasonic irradiator 3 a. The slit 55 has a lengthcorresponding to a diameter of the disc 53.

Based on this structure, because the pin 54 is engaged with the slit 55and is driven to move an end of the ultrasonic irradiator 3 a where theslit 55 has been provided, in accordance with rotation of the rotatingaxis 52, the ultrasonic irradiator 3 a moves up and down in a rangecorresponding to the diameter of the disc 53. Then, because theultrasonic irradiator 3 a has been supported on a side wall of the rigidmaterial 42 by the support member 51, which is freely rotatable, theultrasonic irradiator 3 a can be freely tilted with respect to the planearea 42 a of the rigid material 42, with the support member 51 servingas an axis.

The ultrasonic irradiator 3 a may be driven by a linear motor, awater-powered piston, an electromagnetic moving solenoid orwater-powered motor, etc., instead of using the structure shown in FIG.14 through FIG. 16. Thereby, the ultrasonic irradiator 3 a may bearranged so as to be freely moved along the plane area 42 a of the rigidmaterial 42, or to be freely tilted with respect to the plane area 42 aof the rigid material 42.

Further, in the case where the ultrasonic irradiator 3 a is arranged soas to be freely tilted with respect to the plane area 42 a of the rigidmaterial 42, it is preferable to use an ultrasonic irradiator 3 d inwhich the ultrasonic irradiator 3 a is divided into a unit of subdividedrows, each row having a plurality of ultrasonic transducers 1 a and 1 bas shown in FIG. 17. In the ultrasonic irradiator 3 d, the tilting anglewith respect to the plane area 42 a of the rigid material 42 can be madelarger than that of the ultrasonic irradiator 3 a, and thereby a changeof position, where the ultrasonic waves irradiated from the ultrasonictransducers 1 a and 1 b toward the object overlap within the object, canbe made larger.

In this case, the same structures 52, 53, 54 as shown in FIG. 16 can beprovided for the ultrasonic irradiator 3 d, located at a right-hand sideof the planar bag 41. An end of an ultrasonic irradiator row 3 d and anedge of another ultrasonic irradiator row 3 d are connected by aconnection member 56. Thereby, in accordance with tilting of theultrasonic irradiator row 3 d, which is engaged with the slit 55, thepin 54 arranged in the disc 53 can drive the other ultrasonic irradiatorrows 3 d simultaneously, to tilt them with respect to the plane area 42a of the rigid material 42.

In FIG. 14 to FIG. 16, and in FIG. 18, the ultrasonic transducers 1 aand 1 b have not been shown for simplicity in illustration.

In the ultrasonic irradiation apparatus of the present embodiment, anplane of the planar bag 41, which is opposed to the living body 6, maybe composed of a flexible material instead of the rigid material 42. Itis preferable that the flexible material has a fine flexibility in onedirection, but, when deformed in one direction, it becomes difficult tobe deformed in a direction transverse to the deformation.

Therefore, when using a flexible material 57 being fairly hard, insteadof the rigid material 42, the flexible material 57 is slightly hard andis bent so as to form waves, wherein the bent portions are constructedof linear recesses 58, as depicted in FIG. 19. The top upper openportions of the linear recesses 58 can be deformed apart, and therebythe planar bag 41 also is deformed in a direction transverse to thelinear recesses 58. In order to conform to curved surfaces of a livingbody, an output window composed of the soft material 43 is deformed inthe direction of the linear recesses 58. In this case, the range atwhich the output window composed of the soft material 43 becomesdeformed is smaller, and the thickness of the fluidic material 44 mayalso be smaller and lighter than in the case of FIG. 17.

Thus, the planar bag 41 can be deformed three-dimensionally, and theultrasonic transducers 1 a and 1 b installed inside of the ultrasonicirradiator 3 a can be arranged to conform to the three-dimensionallycurved surfaces of the living body 6.

In the structure shown in FIG. 19, it is preferable that the irradiator3 a be freely movable underneath the recesses and in parallel to theliving body 6, as shown by the arrow, in order to change its positionfor averaging, wherein the ultrasonic waves emitted from the ultrasonictransducers 1 a and 1 b toward the object overlap within the object, andare uneven due to the sonic field, based on the arrangement of theultrasonic transducers 1 a and 1 b. For this purpose, a magneticmaterial can be mixed into or attached to the flexible sheet 2 of theultrasonic irradiator 3 a, and magnets can be attached at the bottom ofthe linear recesses 58, to keep them close while moving.

In the ultrasonic irradiation apparatus of the present embodiment, forthe fluidic material 44 contained in the planar bag 41, the same fluidicmaterial as the fluidic material 32 contained in the planar bag 31 shownin FIG. 11, composed of a heatable and/or refrigeratable high specificheat material, can be used. Therefore, in the ultrasonic irradiationapparatus, the effectiveness of irradiating an object with ultrasonicwaves can be enhanced, or the feeling of the object when the object is ahuman can be improved, by using a fluidic material 42 that has beenpreviously heated by, e.g., a microwave oven or cooled by an electricrefrigerator.

In the ultrasonic irradiation apparatus, instead of the ultrasonicirradiator 3 a, the ultrasonic irradiator 3 b shown in FIG. 4 throughFIG. 7, or the ultrasonic irradiator 3 c shown in FIG. 8, can be used.

Next, referring to FIG. 20 and FIG. 21, an ultrasonic irradiationapparatus according to the sixth embodiment of the present inventionshall be explained. The ultrasonic transducers 1 a and 1 b are not shownin FIG. 20 and FIG. 21, for simplicity of illustration.

The ultrasonic irradiation apparatus has a band holding member 61,arranged so that the ultrasonic irradiator 3 a is easily installed, viathe band holding member 61, on a region of the living body 6, such asthe abdominal region or thigh, as depicted in FIG. 20( a) or FIG. 20(b). The band holding member 61 is joined to a periphery of theultrasonic irradiator 3 a, wherein the band holding member 61 is capableof being wound around the living body 6, and is tightly fixed at anappropriate position on the body by a pair of plane fasteners 62 a and62 b, as depicted in FIG. 20( a).

The band holding member 61 can be arranged so as to cover the ultrasonicirradiator 3 a, as depicted in FIG. 20( b). In this case, the ultrasonicirradiator 3 a may be integrally fixed to the band holding member 61, ormay be arranged so as to be optionally detached from the band holdingmember 61 by a pair of plane fasteners (not shown). Further, theultrasonic irradiator 3 a can simply be held in the band member 61merely by friction between the band holding member 61 and itself,without having any means for fixing the ultrasonic irradiator 3 a to theband holding member 61.

Because the ultrasonic irradiator 3 a is fitted to the living body 6 viathe band holding member 61 in the ultrasonic irradiation apparatus, theband holding member 61 greatly assists in reducing the load on anoperator.

Further, it is preferable that the ultrasonic irradiator 3 a be arrangedso as to contact the living body 6 at the side of the flexible sheet 2,as depicted in FIG. 3. Further, the ultrasonic irradiator 3 a can bearranged to have a protective layer on the non-output side thereof, andfurther, a layer of a material such as a fluorocarbon, having a smallcoefficient of friction, can be coated on the surface. Thereby, theultrasonic irradiator 3 a is arranged to be able to slide against theband holding member 61 while the ultrasonic irradiator 3 a is arrangedin contact with the living body 6 via the fluidic material layer 7, andis able to slide against the living body 6 as well. Therefore, theultrasonic irradiator 3 a can be moved along the living body 6 whilepositioned in an intervening manner between the band installation member61 and the living body 6.

Further, the ultrasonic irradiation apparatus preferably has thestructure shown in FIG. 21, so as to be freely movable along the livingbody 6 without being subject to friction of the band holding member 61,namely, being positioned so as not to intervene between the band and theliving body 6.

The ultrasonic irradiation apparatus depicted in FIG. 21 is joined to anedge of the ultrasonic irradiator 3 a without being covered by the bandholding member 61. Rather, a band holding member 63 is provided, whichis to be wound around the living body 6, and winding devices 66 a and 66b are provided that wind strings 65 connected to the ultrasonicirradiator 3 a by means of pulleys 64 driven by a motor (not shown),while additional band holding members 67 a and 67 b are provided to bewound around the living body 6, for fixing the overall assembly. Each ofthe band members 67 a and 67 b has a pair of plane fasteners (not shown)at an edge thereof, and can be tightly fixed to the living body 6 at anappropriate position by means of such plane fasteners.

In the ultrasonic irradiation apparatus depicted in FIG. 21, theultrasonic irradiation apparatus 3 a can be reciprocated along surfacesof the living body 6, in the length direction of the band holding member63, by using a jelly as a lubricant, and by alternatively driving thewinding devices 66 a and 66 b while the ultrasonic irradiation apparatusis fitted to the living body 6 by the band holding members 63, 67 a and67 b.

In the ultrasonic irradiation apparatus shown in FIG. 21, the ultrasonicirradiation apparatus 3 a is freely reciprocated along the lengthdirection of the band installation member 63. However, it may also bearranged so as to be freely reciprocated in the width direction of theband installation member 63.

In the ultrasonic irradiation apparatus, it is preferable that the bandholding members 61, 63, 67 a and 67 b be composed of a flexible materialcapable of absorbing or dissipating sweat. As this material, forexample, a belt composed of fabric or textile, or a fiber net, may beutilized.

Further, in the ultrasonic irradiation apparatus of present embodiment,the ultrasonic irradiator 3 b shown in FIG. 4 through FIG. 7, theultrasonic irradiator 3 c shown in FIG. 8, or the planar bag 41 havingat least one flexible plane, as shown in FIG. 13 through FIG. 19, can beused instead of the ultrasonic irradiator 3 a.

INDUSTRIAL APPLICABILITY

The present invention is applicable, e.g., for use in irradiating aliving body with ultrasonic waves for lipolysis within the living body,and for acceleration of the bloodstream and the infiltration ofmedicines.

1. An ultrasonic irradiation apparatus comprising: an ultrasonicirradiator having a living body contact sheet member beingultrasonically conductive and being flexible and/or elastic; and aplurality of ultrasonic transducers arranged in a planar pattern on oneplane of said living body contact sheet member, wherein thetransducer-arranged plane is apart from a contact plane of said livingbody, wherein said ultrasonic irradiator has at least one of an airbacking layer and a sonic absorbing layer disposed on a back side areaof said ultrasonic transducers, wherein said air backing layer and saidsonic absorbing layer are substantially non-ultrasonically conductiveand formed from materials different from the material constituting saidliving body contact sheet member, and wherein said ultrasonic irradiatorhas a detachable soft material layer on a contact plane of the livingbody contact sheet member, wherein the soft material layer can be heatedor cooled and attached on the living body contact sheet member.
 2. Theultrasonic irradiation apparatus according to claim 1, wherein saidplurality of ultrasonic transducers have ground electrodes disposed on aback side of the living body contact sheet member, all of said groundelectrodes being mutually connected to each other and to a groundelectric potential, and opposed drive electrodes, wherein plural driveelectrodes are connected together in one or more groups mutually to eachother and to a driving electric potential.
 3. The ultrasonic irradiationapparatus according to claim 1, wherein the plurality of ultrasonictransducers are composed of a plurality of drive electrodes arranged onone surface of a flexible piezoelectric sheet member and a plurality ofopposed electrodes arranged on the other surface facing each other. 4.The ultrasonic irradiation apparatus according to claim 1, wherein theliving body contact sheet member comprises a flexible planar bagcontaining a fluidic material being ultrasonically conductive, and thebag further has a pump for periodically changing a volume of thecontained fluidic material and a tube for supplying or discharging thefluidic material.
 5. An ultrasonic irradiation apparatus comprising: anultrasonic irradiator having a living body contact sheet member beingultrasonically conductive and being flexible and/or elastic; and aplurality of ultrasonic transducers arranged in a planar pattern on oneplane of said living body contact sheet member, wherein thetransducer-arranged plane is apart from a contact plane of said livingbody, wherein said ultrasonic irradiator has at least one of an airbacking layer and a sonic absorbing layer disposed on a back side areaof said ultrasonic transducers, wherein said air backing layer and saidsonic absorbing layer are substantially non-ultrasonically conductiveand formed from materials different from the material constituting saidliving body contact sheet member, and wherein said ultrasonic irradiatorcomprises an impedance adjusting means for allocating an outputdistribution over the plurality of ultrasonic transducers, so that asonic intensity of each of said ultrasonic transducers assumes apredetermined respective intensity ratio while said ultrasonicirradiator is flexibly deformed, and wherein said impedance adjustingmeans is arranged in parallel to each transducer or parallel to apredetermined number of said transducers.
 6. An ultrasonic irradiationapparatus comprising: an ultrasonic irradiator having a living bodycontact sheet member being ultrasonically conductive and being flexibleand/or elastic; and a plurality of ultrasonic transducers arranged in aplanar pattern on one plane of said living body contact sheet member,wherein the transducer-arranged plane is apart from a contact plane ofsaid living body, wherein said ultrasonic irradiator has at least one ofan air backing layer and a sonic absorbing layer disposed on a back sidearea of said ultrasonic transducers, wherein said air backing layer andsaid sonic absorbing layer are substantially non-ultrasonicallyconductive and formed from materials different from the materialconstituting said living body contact sheet member, and wherein saidultrasonic irradiator comprises an adjusting inductance, approximatelyresonant to each ultrasonic transducer, so that a sonic intensity ofeach of said ultrasonic transducers assumes a predetermined respectiveintensity ratio while said ultrasonic irradiator is flexibly deformed,and wherein said adjusting inductance is arranged in series with eachtransducer or in series with a predetermined number of transducers. 7.An ultrasonic irradiation apparatus comprising: an ultrasonic irradiatorcomprising a flexible and/or elastic net member; a plurality ofultrasonic transducers installed on the net member and arranged in aplanar pattern, wherein each of said ultrasonic transducers is held bysaid net member only on a non-ultrasonically transmitting back portionand/or a side portion thereof, which is distinct from an ultrasonicallytransmitting face portion of each of said ultrasonic transducers,wherein said net member is constructed by one of flexible and/or elasticfiber strings, rubber strings, metallic chains, hard plastic chains,coiled springs, and rigid rods that are linked together at their ends soas to be freely deformable and rotatable, and wherein said ultrasonicirradiator has a detachable soft material layer on a contact plane ofthe living body contact net member, wherein the soft material layer canbe heated or cooled and attached on the living body contact net member.8. The ultrasonic irradiation apparatus according to claim 7, whereinsaid plurality of ultrasonic transducers have ground electrodes disposedon a back side of the living body contact net member, all of said groundelectrodes being mutually connected to each other and to a groundelectric potential, and opposed drive electrodes, wherein plural driveelectrodes are connected together in one or more groups mutually to eachother and to a driving electric potential.
 9. The ultrasonic irradiationapparatus according to claim 7, wherein the plurality of ultrasonictransducers are composed of a plurality of drive electrodes arranged onone surface of a flexible piezoelectric sheet member and a plurality ofopposed electrodes arranged on the other surface facing each other. 10.The ultrasonic irradiation apparatus according to claim 7, wherein theliving body contact net member comprises a flexible planar bagcontaining a fluidic material being ultrasonically conductive, and thebag further has a pump for periodically changing a volume of thecontained fluidic material and a tube for supplying or discharging thefluidic material.
 11. An ultrasonic irradiation apparatus comprising: anultrasonic irradiator comprising a flexible and/or elastic net member; aplurality of ultrasonic transducers installed on the net member andarranged in a planar pattern, wherein each of said ultrasonictransducers is held by said net member only on a non-ultrasonicallytransmitting back portion and/or a side portion thereof, which isdistinct from an ultrasonically transmitting face portion of each ofsaid ultrasonic transducers, wherein said net member is constructed byone of flexible and/or elastic fiber strings, rubber strings, metallicchains, hard plastic chains, coiled springs, and rigid rods that arelinked together at their ends so as to be freely deformable androtatable, and wherein said ultrasonic irradiator comprises an impedanceadjusting means for allocating an output distribution over the pluralityof ultrasonic transducers, so that a sonic intensity of each of saidultrasonic transducers assumes a predetermined respective intensityratio while said ultrasonic irradiator is flexibly deformed, and whereinsaid impedance adjusting means is arranged in parallel to eachtransducer or parallel to a predetermined number of said transducers.12. An ultrasonic irradiation apparatus comprising: an ultrasonicirradiator comprising a flexible and/or elastic net member; a pluralityof ultrasonic transducers installed on the net member and arranged in aplanar pattern, wherein each of said ultrasonic transducers is held bysaid net member only on a non-ultrasonically transmitting back portionand/or a side portion thereof, which is distinct from an ultrasonicallytransmitting face portion of each of said ultrasonic transducers,wherein said net member is constructed by one of flexible and/or elasticfiber strings, rubber strings, metallic chains, hard plastic chains,coiled springs, and rigid rods that are linked together at their ends soas to be freely deformable and rotatable, and wherein said ultrasonicirradiator comprises an adjusting inductance, approximately resonant toeach ultrasonic transducer, so that a sonic intensity of each of saidultrasonic transducers assumes a predetermined respective intensityratio while said ultrasonic irradiator is flexibly deformed, and whereinsaid adjusting inductance is arranged in series with each transducer orin series with a predetermined number of transducers.